Right lateral decubitus position reduces QT dispersion in patients with chronic heart failure

A greater QT dispersion in patients with chronic heart failure (CHF) appears to be a non-invasive marker of susceptibility to malignant ventricular arrhythmias. We evaluated whether QT dispersion in CHF patients is modified by the patients' recumbent position. In 12 CHF patients, and age and sex-matched 12 normal subjects, a single 12-lead surface ECG was recorded in each postural position [left lateral decubitus position (L), supine position (S), and right lateral decubitus position (R)]. In normal subjects, the QT dispersion was comparable in the three recumbent positions [L: 47+/-15 (SD) ms, S: 40+/-9 ms, R: 38+/-14 ms, P=NS]. In contrast, in CHF patients, QT dispersion was significantly shorter in R than those in L and S (L: 93+/-42 ms*, S: 81+/-29 ms*, R: 63+/-24 ms, *P